My invention pertains to hydraulic pumps; the invention provides an improved pump and is generically applicable to double acting simplex plunger pumps of both broad categories, i.e., "plunger" and "piston" types.
The most relevant prior art of which applicant is aware is U.S. Pat. No. 4,978,284 granted Dec. 18, 1990, the present applicant being one of the coinventors of said prior art patent '284.
My prior art patent '284 provided a number of unique constructions and advantages over the prior art including that cited therein.
My present invention, in turn, provides additional very unique constructions and several very significant advantages over my prior '284 invention. For example, I am able in the present invention to eliminate the crankcase body 30 and the separate head members 80 of patent '284; the body 30 of '284 is a relatively expensive part because all bores therein require precision machining. Thus, one advantage of the present invention is to have fewer parts and thus reduce costs of manufacture and greater simplicity.
Another very significant advantage of my invention is to use the pump drive motor end plate or "end bell" as an integral component of the pump; all prior art pumps of which I am aware (including my prior '284 arrangement) use some form of adaptor means to provide a linkage between the electric drive motor and the pump apparatus. Thus, in patent '284 the crankcase body 30 was a form of adaptor to provide a linkage and connection between the motor 107 and the pumping apparatus, i.e., stuffing boxes 60, head members 80, manifold 50 and plunger member 96.
Another unique aspect of my invention is that I provide a specially shaped pair of unitary combined stuffing box and head members which, together with a double ended plunger member as a subassembly are sandwiched between the flat or planar axial end face of the drive motor and a bottom flat or planar surface of a unitary manifold member.
My unique pump design provides excellent and economical performance and is attainable at an extremely low manufacturing cost in comparison to all prior art pumps of which I am aware.